Hydrogen is considered closest to the next green energy source as it emits only oxygen and water. There are different methods through which gray, blue, and green hydrogen are produced. The process and type of hydrogen produced depend on the energy source and carbon emission. Out of these, green hydrogen production is the most eco-friendly method without any CO2 emissions. Thus, researchers are looking for a way towards enhanced green hydrogen production from active MXenes.
A research team from the Korea Institute of Science and Technology (KIST) led by Dr Albert Sung Soo Lee in collaboration with the group of Professor Chong Min Koo at Sungkyunkwan University, has developed an oxidatively stable molybdenum-based MXene as electrocatalyst support in anion exchange membrane water electrolyzers.
The recently published report highlights how MXene is stable against oxidative high-voltage conditions. The experiment shows Mxene can be used as an oxygen evolution reaction electrode material for producing green hydrogen. This can reduce its cost of production too.
Green Hydrogen Production and Need of MXene
A lot of energy is required to split water into hydrogen and oxygen molecules. A catalyst with tiny nanoscale particles providing a larger surface area for reaction can lower the energy required by the process.
However, hydrogen production efficiency reduces over time as catalyst particles agglomerate. To prevent this carbon is mainly used as a cathode but it oxidizes to CO2 during anode’s oxidation reaction.
Thus, Mxene, the nanomaterials are used as supports. As they are composed of metal atoms (Mo, Ti, Ta, Hf, etc.), and carbon or nitrogen atoms, they exhibit electrically conductive properties. Also, they have a 2D nanostructure that is suitable to support the catalyst. These features make them favorable for hydrogen production.
In another research, UT’s researchers are developing hydrogen fuel from iron-rich rocks.
Highlights: Enhanced Green Hydrogen Production from Active MXenes
- MXenes are titanium-based and due to their atomic nature, they easily oxidize in water. This led to the inherent disadvantage of the catalyst to being unable to maintain high electrical conductivity.
- To overcome this limitation, the team developed a molybdenum-carbide-based MXene as a supporting catalyst.
- Molybdenum-based MXene creates strong bonds between molybdenum atoms and active materials cobalt on the surface.
- Hydrogen production is increased by 2.45 times due to the chemical bonds resulting from the reaction.
- Cell durability improves by 10 times in comparison to the results of the latest titanium-based MXene (which was less than 40 hours).
- The new approach reduces the cost of production of green hydrogen.
- It will be applied to large-scale hydrogen production plants and power stations.
Another Green Energy Breakthrough: Catalyst lowers iridium use by 95% in hydrogen electrolyzers.
Dr Albert Sung Soo Lee of KIST says, “By controlling the elements that makeup MXene, we were able to find suitable candidates for green hydrogen production environments, and through this, we secured a stable MXene support in an oxidizing environment.”
“In the future, we will contribute to the revitalization of the hydrogen-based economy by developing oxygen-generating electrode catalysts with catalytic efficiency and durability,” Dr. Lee added.